The Puck criteria are meanwhile widely used and accepted as state of the art in IFF-analysis. A number of guidelines refer to the Puck criteria. This list includes the VDI-guideline VDI2014, Part 3 [VDI 2006] on the Development of FRP components, the Guideline for the Certification of Wind Turbines of Germanische Lloyd [Germanische Lloyd 2003] and the Det Norske Veritas Guideline DNV-RP-F202 on the use of Composite Risers in Offshore applications [DNV 2003]. In contrast to this, the application of the complete Puck theory including the post failure analysis is not yet as widely spread. For some standard problems in composite design such a detailed analysis is indeed not needed. However, cases for which only a state of the art post failure analysis would detect the realistic behavior of the structure are often not even detected as critical. A simple example of this is a ±55° tube for internal pressure as it is discussed in the chapter “Experimental work”. The use of design and FEM-software which has the complete theory implemented would for sure help avoiding failure of structures in practice which today happen in some cases because the structural problems have not been realized in the design phase, because they are only detectible by very experienced Composite designers and/or the application of a state of the art post failure analysis.